共查询到17条相似文献,搜索用时 530 毫秒
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【目的】通过采取栽培管理措施提高川西云杉Picea likiangensis var. rubescens幼龄采穗母树穗条产量和质量,为优化云杉幼龄母树栽培管理措施提供参考依据。【方法】在甘肃省小陇山沙坝国家云杉种质资源库川西云杉超级苗(实生苗)采穗圃,选择树势基本一致的8年生采穗母树,于芽萌动前(4月中旬),采用随机区组试验设计,进行修剪、修剪+摘芽、修剪+保留枝条(1/3长、1/2长、2/3长)等处理,研究其对采穗母树穗条数量、质量和冬芽数的影响。11月调查试验母树上当年生长度≥5 cm的枝条数量、质量(基部直径和长度)和冬芽数(含可发育成枝条的隐芽)。【结果】不同处理对川西云杉母树当年顶层轮生枝主干上的长短枝数量的影响差异不显著(P> 0.05),对其他枝条数量的影响差异显著(P <0.05)。不同处理后采穗母树当年生长度≥5 cm的总枝条数均显著低于对照,但母树当年新生枝条的增粗和伸长生长均被促进,随着新生枝条的伸长,枝条上的平均芽数增多。不同处理中,修剪+摘芽的处理效果最好,其枝条基部平均直径达到(5.29±1.22)mm,平均长度为(16.28±3.30)cm,... 相似文献
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日本落叶松母树修剪的技术,近年来,广大林业工作者曾提出很多技术上的探讨,取得了一定的经验。而对老枝更新复壮,树冠循环更替,至今国内外尚无比较成熟的方法和经验。我们在实践中发现,日本落叶松母树采取“强度整枝”,可以刺激休眠芽萌发出新的枝条,实现老枝更新复壮,树冠循环更替,使母树永续结实。“强度整枝”方 相似文献
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2种修剪方式对红松生长量的影响 总被引:1,自引:0,他引:1
通过对红松人工林进行截顶和修枝2种修剪试验,研究不同修剪方式对红松生长量的影响,结果表明:密度适中的林分截顶后能促进林木直径的生长,试验区比对照区提高了30.8%;适当的修枝(修去枯死枝和下层1~2轮活枝)不仅可以提高林木的质量,还可以提高林木直径的生长量。 相似文献
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就不同修剪强度对二次结实板栗生长发育的影响作了试验研究,结果表明对于板栗结果母枝的修剪以1/3、1/4和1/2修剪强度能极显著减少雄花数量,1/4和去顶处理具增加雌花数量效应,1/3、1/4和去顶处理均具一定的抑制新梢伸长生长和促进枝粗生长作用,1/4修剪强度和去顶处理具增加第一次结蓬数量效应,1/2修剪处理则使二次结实板栗结蓬数量大大降低,此外,随修剪强度的增加其第二次结蓬数也增加,至1/3修剪强度时达到峰值. 相似文献
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修剪,授粉等措施对樟子松种子园母树结实的影响 总被引:1,自引:0,他引:1
在樟子松种子园中,对母树进行修剪、授粉等促进母树结实的试验,结果表明,中度修剪平均单株雌球花数量比对照增加13.37%,单株球果数增加14.30%,空种子占成种子比例减少了2.24%;强度修剪平均单株种子产量下降了27.02%,空种子占成种子比例减少了3.48%。母树开花期间,进行了人工辅助授粉1次和3次,平均单株种子产量分别为对照的145.12%和171.95%。喷施50mg/kg的赤霉素药液, 相似文献
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The effects of top pruning on subsequent seed and pollen cone production in lodgepole pine (Pinus contorta Dougl.) grafted clones in two seed orchards were evaluated. In the older orchard (14 years old), three pruning regimes were applied: an untreated control, a moderate pruning where 25% of the crown was removed and a severe pruning where 40% of the crown was removed. In the younger orchard (ten years old), only a control pruning and a severe pruning (50% of crown removed) were applied. Five-year seed cone production was lower in treated ramets compared to controls in both orchards. However, when cumulative seed cone yields were adjusted for reduced tree heights after pruning, differences were no longer significant in the older orchard. Strong clonal variation was observed in seed cone yields in both orchards. Pollen cone development was less variable among treatments in the older orchard. In the younger orchard, controls consistently produced heavier pollen crops. Pruning recommendations for similar orchards are made and results discussed for reducing the impacts of losses in seed cone yields.Deceased 相似文献
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Long term cone production and growth responses to crown management and gibberellin A4/7 treatment in a young western hemlock seed orchard 总被引:1,自引:0,他引:1
Stephen D. Ross 《New Forests》1989,3(3):235-245
At age 5–6 years, rooted cuttings in a western hemlock (Tsuga heterophylla) clonal seed orchard received either a severe (ST) or moderate (MT) top pruning (upper 50 and 25% of live crown removed, respectively), or were left untopped (UT). Over the following 6 years, UT trees increased in height from 1.5 to 3.9 m, whereas through annual and biennial top and side pruning, MT trees grew to 2.2 m and ST trees were maintained at 2.0 m. Crown pruning had no effect on the subsequent annual production of seed or pollen cones. Spray applications of gibberellin A4/7 in years 2 and 4 of the study increased 5-fold and 2-fold the percentage of trees producing a medium and greater crop, respectively, of seed and pollen cones in each year 3 and 5. 相似文献
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By taking three forecasting methods (sample trees, sample branches and climate factors prediction) the forecasting equation
of seed were established through correlation analysis and regression analysis on seed crop of Qingshan and QinheLarix olgensis seed orchard. The research results showed that it gave more accurate prediction with less working load by taking pistillate
numbers of four sample branches at middle layer of crown to predicate seed crop. And the short-term prediction equation of
this method was established. The correlation analysis between seed crop and climate factors showed that the relative humidity
May and June, annual evaporative amount, and accumulated temperature above 10°C, possess the highest effect on bud differentiation
and seed crop, then the middle-term predication equation of climate factors was established. 相似文献
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对油松不同采种时期对种子质量影响问题进行了试验研究 ,结果表明 ,各种处理即不同的采种时期对种子质量影响明显 ,从 8月 15日开始 ,到 9月 2 9日的处理 ,种子千粒重、发芽率、发芽势差别极显著。从 8月 15日到 9月 14日种子质量虽有显著差异 ,但都属于不合格种子 ;从 9月 14日到 9月 2 9日种子都达到省标和国标 ,但种子质量随生长期延长 ,种子质量逐渐提高。综合研究可以确定油松最佳采种时期应为 9月 19~ 2 9日 相似文献
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A juvenile radiata pine clonal seed orchard (Pinus radiata D. Don) in Sergude (northwestern Spain), comprising 57 clones, was evaluated for fertility, offspring diversity and genetic drift during 4 years. Flower and fruit production was used to asses clone fertility in the orchard. Fertility variation measured as “sibling coefficient” was found to be an average of 1.5, having high genetic diversity (0.99) and low coancestry (0.013). The clones varied in fertility from year to year. Effective population size in the orchard was between 35 and 40, indicating that between 60.30 and 69 %, the clones contributed effectively to seed yield. One way to improve seed yield in the orchard is by increasing the effective population size. Thinning and pruning highly reproductive clones of gibberellin application might be useful in increasing effective population size. The orchard’s parental balance showed consistent improvement over time. Cone and seed characteristics were also investigated. The results showed that significant genetic variation exists among clones for cone width and length; total, sound and empty seed number; as well as 100 seed weight. The seed orchard is still in a juvenile phase; moreover, the broad-sense heritability and variation data obtained in this study could be very valuable in the management practices of the existing radiata pine clonal seed orchard and can be also used for better planning of advanced generation of clonal seed orchards in Spain. 相似文献